Baltimore police ordered every officer to work July 4 and will rely heavily on reinforcements from state law enforcement agencies, an effort intended to keep Inner Harbor visitors safe while maintaining a strong presence in areas besieged by recent violence.

The city has traditionally packed downtown with officers for Independence Day celebrations like the one planned for Thursday. But this year police are also stepping up their presence in neighborhoods across the city that have been rocked by more than 40 shootings and 16 homicides since June 21.

"The Inner Harbor is going to be safe on the Fourth of July," Lt. Col. Darryl DeSousa declaredat a news conference

DeSousa promised an "overflood" of officers downtown and said that all police districts would be at full strength, because the department has canceled leave for the holiday.

A visible army of city and state police, city sheriff's deputies and Maryland Transportation Authority Police officers will be posted downtown as about 200,000 people fill the Inner Harbor at dusk to watch fireworks burst over the water.

Revelers will see police on foot and on horseback, patrolling in cars and peering from helicopters. Undercover officers will mix with the throngs while investigators monitor multiple angles from overhead CitiWatch cameras and "surveillance" stages.

The Inner Harbor celebration runs from 4 p.m. to 10 p.m. The fireworks display is scheduled for 9:30 p.m.

While city police have been grappling with a persistent deficit of officers due to retirements, defections and suspensions, Mayor Stephanie Rawlings-Blake has made it clear to Police Commissioner Anthony W. Batts that he has her "full support," mayoral spokesman Ryan O'Doherty said.

O'Doherty said police would have technological resources needed "to target repeat violent offenders, gangs, and illegal guns while keeping our streets — including downtown — safe." He noted that the CitiWatch camera network, which the mayor has expanded, acts as a "force multiplier" that helps officers with more eyes on the street.

As the city seeks to balance the needs of well-off enclaves with those of troubled neighborhoods, community leaders said the holiday represents one of the biggest tactical challenges Batts has faced since being hired last fall.

"This may be the real first test of whether downtown and uptown Baltimore is covered as well as all areas," said former Baltimore NAACP president Dr. Marvin L. "Doc" Cheatham Sr.

While police annually call upon other area law enforcement agencies for special events, they are relying even more on them to meet that challenge.

Kirby Fowler, president of the Downtown Partnership, which promotes business, residency and tourism, said he's been told Baltimore police can handle all the assignments.

"We've received assurances that their levels will be where they've been at in other years and that their focus will be on the thousands upon thousands of people and residents coming into downtown," he said.

City leaders believe the inter-agency cooperation and downtown enforcement strategies will prevent a repeat of past violence that has tarnished Baltimore celebrations.

After a tourist was fatally stabbed at Pier Six and a 4-year-old wounded by celebratory gunfire after 2011 Independence Day events, police created a perimeter of bike-rack fencing to corral Inner Harbor spectators for easier monitoring and crowd control.

Police will use the same fencing this year, which officials credit with helping to keep city celebrations relatively peaceful.

The string of quiet events ended when violence marred the Baltimore Ravens' Super Bowl victory parade this year. A few hours after the Feb. 5 celebration ended and as parade-goers continued to mill around downtown, a large fight at West Fayette and North Howard streets ended with 15-year-old De'ontae Smith fatally stabbed and two other teens injured. The fight occurred three blocks from the parade route.

DeSousa acknowledged Wednesday that police "caught violence on the outskirts" that day and plan to expand their tactical footprint to stretch along the downtown waterfront north to Fayette and out to Fells Point.

On the city's east and west sides, police will continue doubling and even tripling the number of officers on patrol to suppress the recent wave of shootings.

Councilman Brandon Scott called Thursday a "test" for the department. He worried that officers are being pushed too hard while the agency battles a long-standing attrition problem that has thinned its ranks over the past few years.

Police are currently operating with one-sixth fewer sworn officers than they are supposed to have.

"I am very concerned about the officers being tired and their health and their safety," he said. "We have to make sure that we're not running them into the ground so they can be healthy and take care of their own lives and families."

While checking on special deployments throughout the city earlier this week, Batts said he was pleased with how police were able to slow the violence last weekend by "getting in front of" retaliatory shootings or learning who might act out in retaliation after someone was killed or injured.

He said all divisions and districts are operating much more "in sync," communicating and relaying important information, after residents and leaders criticized police's initial response to the outburst late last month, including two homicides that occurred on the same block a week apart.

Cheatham said he's "optimistic" about how Batts has been handling the spike in street violence. He praised the commissioner and top commanders for being visible and accessible to residents across the city.

"I like what I'm hearing from the commissioner," Cheatham said. "He's listening to us as community leaders and residents."

He said community cooperation with police has picked up, and he challenged residents to continue to serve as eyes and ears on city blocks Thursday while police try to cover as much territory as possible, including his West Baltimore block.

"This may be the real first test for the commissioner," Cheatham said. "But not whether they will have enough deployment downtown in Baltimore but whether there'll be enough officers here."